September 25, 2013

New Electric Fish Discovered In Remote South America

A new species of electric fish has been discovered in the murky waters of the upper Mazaruni River in South America.

Scientists reported in the journal Zoological Scripta that they discovered a species that they've dubbed Akawaio penak in the remote regions in northern Guyana during an expedition. The team analyzed tissue samples collected during the trip, and found that the fish represents not only a new species but also a new genus.

Electric fish, known for their ability to generate electric fields, are found in both oceans and freshwater. A number of fish, including sharks and rays, can detect electric fields, but they are not classified as an electric fish because they do not generate their own electricity.

Like other electric fish, Akawaio penak has a long organ running along the base of its body that produces the electric field. The electric field is too weak to stun prey and is used instead to navigate, detect objects and communicate with other electric fish.

Fish that generate electric fields typically use them to detect perturbations in the field, such as an object passing by. They are also able to use the field to communicate with members of their own species through high frequency electric "chirps." Scientists say that these fish are very cryptic and that their signaling 'language' is difficult to decipher.

The weak electric fields can be thought of in the same way as the sounds that bats emit in echolocation. Scientists are able to record these signals, analyze them and then mimic them in order to measure the recipient's behavioral response to the signal.

The upper Mazaruni River, where the fish was discovered, is a hotspot for biological diversity. However, the region still remains largely unexplored because of its remote location. The area contains countless rivers on top of a series of uplands that have remained isolated for more than 30 million years. This region is increasingly suffering from freshwater habitat degradation due to gold-mining in the area.

"The fact this area is so remote and has been isolated for such a long time means you are quite likely to find new species," University of Toronto Scarborough professor Nathan Lovejoy said in a statement. "The Mazaruni contains many unique species that aren't found anywhere else in the world. It's an extremely important area in South America in terms of biodiversity."